AQP4 and Hypoglycemia: Papadopoulos and Verkman (2013) found that AQP4-M23 is enriched in the core of OAPs, and AQP4-M1 in the periphery. In addition, increased proportion of AQP4-M1/M23 in oocytes led to disorganize OAPs (Furman et al., 2003). It has been documented that OAPs plays a role in the AQP4 polarity to astrocyte endfeet (Frydenlund et al., 2006; Noell et al., 2009). Furthermore, AQP4-M1/M23 ratio was found to be elevated with the increase of total AQP4 protein expression after hypoglycemia which may cause disorganization of the OAPs and loss of AQP4 polarity (Deng et al., 2014).